using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;

namespace StellaOps.Determinism;

/// <summary>
/// Extension methods for registering determinism abstractions in DI.
/// </summary>
public static class DeterminismServiceCollectionExtensions
{
    /// <summary>
    /// Adds <see cref="TimeProvider.System"/> as a singleton.
    /// </summary>
    public static IServiceCollection AddSystemTimeProvider(this IServiceCollection services)
    {
        services.TryAddSingleton(TimeProvider.System);
        return services;
    }

    /// <summary>
    /// Adds <see cref="SystemGuidProvider"/> as the <see cref="IGuidProvider"/> singleton.
    /// </summary>
    public static IServiceCollection AddSystemGuidProvider(this IServiceCollection services)
    {
        services.TryAddSingleton<IGuidProvider, SystemGuidProvider>();
        return services;
    }

    /// <summary>
    /// Adds both <see cref="TimeProvider.System"/> and <see cref="SystemGuidProvider"/> as singletons.
    /// This is the recommended setup for production services.
    /// </summary>
    public static IServiceCollection AddDeterminismDefaults(this IServiceCollection services)
    {
        services.AddSystemTimeProvider();
        services.AddSystemGuidProvider();
        return services;
    }
}